This invention relates to detergent bars having a perfumed plastic core. More particularly, it relates to detergent bars intended for conventional toilet soap uses either as hand soaps or bath or shower soaps which are elastic or inelastic in nature but which contain a solid perfumed plastic core giving them unique properties which alleviates wastage thereof and causes the aroma in the environment surrounding the soap, on use thereof, to be aromatized in an aesthetically pleasing manner.
A wide variety of materials have been incorporated into soap and synthetic detergent compositions. Soap bars have included perfumes, colorants, abrasives, bleaches, fillers, emollients and bodying agents and among the bodying agents, gelatin is one that has been utilized in the past. Soap bars have usually contained a lower polyhydric alcohol such as glycerol and additionally water, both of which are produced and utilized in the soap making process.
In U.S. Pat. No. 4,181,632 issued on Jan. 1, 1980, there is disclosed an elastic detergent bar useful as a functional article and bath plaything including a synthetic organic detergent which is either an anionic detergent or a amphoteric detergent, gelatin and water. It is further indicated in U.S. Pat. No. 4,181,632 that when the synthetic anionic detergent is employed, a cross-linking or denaturing agent for the gelatin is also present and the articles made in bar or cake form are useful detergents and substantially form-retaining. It is further indicated that although these articles wear away somewhat during their use, they retain their general shapes and elasticities for major proportions of their useful lives. In general, U.S. Pat. No. 4,181,632 defines a hand squeezable elastic solid molded detergent product comprising from about 10 to 80% of synthetic organic detergent selected from the group consisting of anionic, sulfated and sulfonated synthetic organic detergents and amphotetic synthetic organic detergents, said anionic, sulfated and sulfonated synthetic organic detergents being water soluble and selected from the group consisting of alkali metal, triethanolamine and ammonium linear higher alkyl benzene sulfonates, paraffin sulfonates, olefin sulfonates, higher fatty alcohol sulfates, monoglyceride sulfates and high fatty alcohol polyethylene glycol sulfates and mixtures thereof and the amphoteric detergent being water soluble and selected from the group consisting of betaaminopropionates, betaiminodipropionates and imidazolium salts and mixtures thereof, about 5 to 30% of gelatin, about 5 to 60% of water and about 1 to 5% of a compound selected from the group consisting of cross-linking agents and denaturing agents for the gelatin and mixtures thereof when the synthetic organic detergent is an anionic detergent which product is sufficiently squeezable and elastic so that a 2 cm thickness thereof can be pressed between a thumb and forefinger to a 1 cm thickness and upon release of such pressure, will return within 5 seconds to within 1 mm of the 2 cm thickness. U.S. Pat. No. 4,181,632, however, does not contemplate such a detergent bar containing a solid plastic core which is perfumed.
In Belgian design patent No. 877,711 there is disclosed a smooth egg-shaped core of hard plastic material which is molded in the center of a tablet of soap. It is further indicated that the soap from the composite tablet can then be used until the core is washed clean. It is further indicated that this obviates the wastage of soap which normally occurs as a conventional soap tablet becomes very thin. The said Belgian patent No. 877,711, however, does not indicate the utilization of a perfumed plastic core for such soap nor does it indicate the highly efficient process for producing same on the large scale as set forth herein.
In German Offenlegungsschrift No. 3,022,003, there is disclosed a bar of high quality or toilet soap of an appropriate form containing inside of it a two-part hollow capsule. The capsule may be spherical and/or may correspond to the external shape of the piece of soap itself. It is further disclosed in said German Offenlegungsschrift No. 3,022,003 that preferred materials for the capsule are soft plastics or duroplastics and the capsule itself may be externally coated with a soap material harder than that of the remainder of the bar. It is further disclosed in German Offenlegungsschrift No. 3,022,003 that the soap is intended especially for children, the internal capsule being easily taken apart after the soap has been consumed. It is indicated that inside the capsule, there may be an attractive figure or toy and it is thus an incentive for the child to use a bar of soap in order to reach the figure contained within it by contrast to the conventional idea where a bar of soap in the form of a figure rapidly loses that appearance as it is consumed.
In U.S. Pat. No. 4,297,228, there is disclosed a decorative soap comprising a soap with a synthetic resin layer formed on one side of the soap, a strippable layer having a printed layer expressing a pattern such as a design or letters and an adhesive layer which binds the synthetic resin layer to the strippable layer. Furthermore, it is disclosed in said U.S. Pat. No. 4,297,228 that another synthetic resin layer is further laminated on the strippable layer; preferably a layer of transparent soap is press-stuck on the strippable layer interposing a synthetic resin layer. The synthetic resin layer consists of a thin film formed by a thermoplastic resin such as acrylic resin, polyvinyl chloride resin, polypropylene or polyethylene. The strippable layer consists of cellulose resin or silicone resin. The film base material is a synthetic resin film which may be polyethylene, polyester terephthalate and prolypropylene.
U.S. Pat. No. 4,318,878 discloses a process for the production of a compound bar of soap, said bar comprising a primary piece of soap and at least one secondary piece of soap embedded therein, said process comprising:
(a) extruding said primary piece and each said secondary piece at an extrusion temperature of 35.degree. to 45.degree. C,
(b) cooling each said secondary piece below said extrusion temperature to a cooled temperature of 25.degree. to 35.degree. C.,
(c) forming a cavity in the surface of said primary piece prior to said embedding adapted to receive at least one said secondary piece,
(d) embedding each said secondary piece in a cavity, said primary piece having a viscosity low enough to permit flow during embedding, and said secondary piece having a viscosity high enough to substantially prevent flow during embedding.
In U.S. Pat. No. 2,360,920 there are disclosed soap buds made from an aerated aqueous solution of soap containing glycerine and a demulcent, such as may be made from a mixture of Irish moss and gelatin. U.S. Pat. No. 3,689,437 teaches the manufacture of maleable and nonhardenable detergent products from certain percentages of fatty acid isethionates, water, gelatin and hydrocarbon with a filler being optionally present. The resulting bars which may also contain glycerol or propylene glycol and other adjuvants are said to be moldable and extrudable but not elastic (apparantly the elasticity is destroyed upon incorporation of the isethionate into the composition). U.K. Pat. No. 731,396 describes the manufacture of a shaped organic soapless detergent composition in which the organic soapless detergent such as triethanolamine alkyl benzene sulfonate is dispersed in the gelatin gel. Aeration of the gel to produce a frothy product is suggested as are the addition of various builders, fillers, nonionic detergents and the like.
Although the prior art has recognized that a plastic core can be incorporated into soap to prevent wastage and that an elastic soap bar may be produced and also that gelatin may be included in detergent compositions which may be desirably molded or shaped to bar or cake form, the teachings of the art as a whole do not result in bars satisfying applicants standards which require that the bars be form-retaining, sufficiently resistant to breakage and distortion during shipping, storage and use and have a continuous propensity to aromatize the environment surrounding the tablet on use as a result of the aromatizing agent being present in the internal plastic core.